Hi all, I observe a difference between the WKT exports of OSRImportFromEPSG(osr, 3857) and OSRImportFromProj4(osr, "+init=epsg:3857"). The former gives a named coordinate system, the latter gives an unnamed coordinate system.
Case 1: OSRImportFromEPSG(osr, 3857) OSRExportToWkt(osr) 'PROJCS["WGS 84 / Pseudo-Mercator",GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]],PROJECTION["Mercator_1SP"],PARAMETER["central_meridian",0],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],EXTENSION["PROJ4","+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs"],AUTHORITY["EPSG","3857"]]' Case 2: OSRImportFromProj4(osr, "+init=epsg:3857") OSRExportToWkt(osr) 'PROJCS["unnamed",GEOGCS["unnamed ellipse",DATUM["unknown",SPHEROID["unnamed",6378137,0],EXTENSION["PROJ4_GRIDS","@null"]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433]],PROJECTION["Mercator_2SP"],PARAMETER["standard_parallel_1",0],PARAMETER["central_meridian",0],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["Meter",1],AUTHORITY["EPSG","3857"]]' Am I wrong to understand the semantics of "+init=epsg:3857" as "open the epsg database, get entry 3857, and use that"? Is this different from specifying the entry directly? Thanks in advance, -- Sean Gillies
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